Manually operated on-off valve comprises molded plastic housing with inlet and outlet, together with cylindrical opening in which plastic rotatable cut-off component is molded

摘要

The manually operated on-off valve comprises a molded plastic housing (1) with an inlet (2) and an outlet (3), together with a cylindrical opening (4), in which a plastic rotatable cut-off component (5) is molded. In a first position, the cut-off component prevents flow from the inlet to the outlet and in a second position allows flow to take place via a passage (6) which it contains. The cylindrical opening at opposite ends has an outwardly facing conical surface (7), which works in conjunction with a corresponding conical surface on the cut-off component. The cut-off component is molded in such a way that when it cools it shrinks more than the housing so that the cross-section of the housing opening deviates from the circular shape and the extent of the cut-off component at right-angles to the passage is slightly greater than in the passage direction.